18405224 has 24 divisors (see below), whose sum is σ = 36427410. Its totient is φ = 8716896.

The previous prime is 18405223. The next prime is 18405229. The reversal of 18405224 is 42250481.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 13032100 + 5373124 = 3610^2 + 2318^2 .

It is a junction number, because it is equal to n+sod(n) for n = 18405193 and 18405202.

It is not an unprimeable number, because it can be changed into a prime (18405223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 299 + ... + 6074.

Almost surely, 2^18405224 is an apocalyptic number.

It is an amenable number.

18405224 is a deficient number, since it is larger than the sum of its proper divisors (18022186).

18405224 is a wasteful number, since it uses less digits than its factorization.

18405224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6417 (or 6394 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 26.

The square root of 18405224 is about 4290.1310003309. The cubic root of 18405224 is about 264.0262064588.

The spelling of 18405224 in words is "eighteen million, four hundred five thousand, two hundred twenty-four".